Hello @TracyN. Where did you get your PUK code? Also, is the phone specifically asking for a PUK code or is it asking for another type of code? If you would like us to confirm your PUK code, please send us a private message confirming your phone number, full name, and date of birth.
I have the same problem. My phone (Galaxy S7) is asking for my PUK code, yet it only allows 8 digits. My PUK code has 16 digits. I retrieved my PUK from the My Services page, as instructed on the Optus help page.